Most faucets made prior to 1940 did not have replaceable seats. You either had to resurface them, or tap them out for a replacement seat. Any good service plumber should have the equipment to do either one.

: I have a home that was built in 1899. The valves on the bathtub have leeked for years. Local plumbers say the sets are bad and can not be replaced. I have not been able to find any valves that have the proper dementions. Any suggestions? I am trying to maintain the house as orinal so I do not want to change the bathroom because of the valves. I even considered custom built valves but have not been able to locate a resource. Any ideas?